This invention relates to improvements in the construction, design and performance of portable heaters, particularly those which use LP gas as a fuel. Accordingly, it will be herein illustrated in this context, by way of example and not by way of limitation. The improvements of this invention solve and alleviate a number of problems evidenced in the use of prior art portable heaters of this type. Such problems include and have included one or more of the following:
a. difficulties in the manufacture and/or assembly of critically related parts; PA1 b. difficulties in achieving an effective and consistent pattern in the mixing of air and fuel so as to insure proper performance as to combustion; PA1 c. difficulties in achieving flame retention to the rear head of the combustion chamber; PA1 d. ignition problems; PA1 e. difficulties in insuring safety as to use. The incidence and degree thereof have limited the application and usage of LP gas burning portable heaters.
The above and other problems are solved in use of embodiments of the present invention.
As a matter of fact, the present invention enables LP gas burning portable heaters to have a range of BTU output and safety in use which significantly exceeds that believed possible at the price level at which these heaters can be sold.
The prior art which appears to be most pertinent as far as the present inventors are aware consists of the following U.S. Pat. Nos. 4,244,349, Velie et al. Jan. 13, 1981; 3,645,512, Dent, Feb. 29, 1972.
Velie et al shows the use of a multi-apertured rear head for a combustion chamber projected inwardly of which is a fuel nozzle. There is a flame spreader. However, Velie et al requires the use of two combustion chambers and the rear head employed is required to have a multiplicity of rings of apertures which are critically spaced in a radial sense. Furthermore, Velie et al insist on the criticality of a particular dimensional relation of parts which the present invention denies, thus negating special pertinence on its part.
Dent shows a rear head for a combustion chamber having four right angled air scoops in connection with and circularly spaced on its outer face in a concentric relation to its intake opening 26 and a nozzle which is dictated to be hexagonally configured in cross section for a critically positioned application thereof to its mounting plate. Dent also requires a baffle at the outlet end of its combustion chamber.
As will be seen the disclosures of the noted patents offer background information but neither reveal or anticipate the points of novelty of the present invention.
Attention is also directed to U.S. Pat. No. 4,313,417 and application for U.S. Pat. No. 384,868 to which reference is made in respect to certain known detail of the heater herein illustrated. However their disclosures are not pertinent to the points of novelty herein set forth.